WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!

\(\begin{pmatrix} -2 & 1 \\ 2 & 3 \end{pmatrix}\) \(\begin{pmatrix}p & q \\ r & s\end{pmatrix}\)...

Mathematics
JAMB 2008

\(\begin{pmatrix} -2 & 1 \\ 2 & 3 \end{pmatrix}\) \(\begin{pmatrix}p & q \\ r & s\end{pmatrix}\) = \(\begin{pmatrix} 1 & 0 \\0 & 1 \end{pmatrix}\). What is the value of r?

  • A. -\(\frac{1}{8}\)
  • B. \(\frac{3}{8}\)
  • C. \(\frac{5}{8}\)
  • D. \(\frac{1}{4}\)
JAMB CBT Mobile App 2025 - Free Download
JAMB CBT Software 2025 - Free Download
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
Correct Answer: Option D
Explanation

-2p + r = 1.......(i)

2p + 3r = 0.......(ii)

r - 1 + 2p ........(iii)

2p + 3(1 + 2p) = 0

2p + 3(1 + 2p) = 0

2p + 3 + 6p = 0

3 - 8p = 0 \(\to\) 8p = 3

p = \(\frac{3}{8}\)

6 = 1 - 2 \(\frac{3}{8}\)

= 1 - \(\frac{6}{8}\)

\(\frac{8 - 6}{8}\) = \(\frac{2}{8}\)

= \(\frac{1}{4}\)

There is an explanation video available below.


Report an Error Ask A Question Download App
JAMB CBT Software 2025 - Free Download
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT Mobile App 2025 - Free Download
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076

Explanation Video

JAMB CBT Mobile App 2025 - Free Download
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT Software 2025 - Free Download
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076

Contributions ({{ comment_count }})

Please wait...

{{ settings.no_comment_msg ? settings.no_comment_msg : 'There are no comments' }}

Quick Questions

Post your Contribution

Please don't post or ask to join a "Group" or "Whatsapp Group" as a comment. It will be deleted. To join or start a group, please click here

{{ quote.posted_by.display_name }}
{{ settings.form_textarea_description }}
 
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
JAMB CBT Software 2025 - Free Download
JAMB CBT Mobile App 2025 - Free Download
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT Mobile App 2025 - Free Download
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
JAMB CBT Software 2025 - Free Download